Professor Alexis Jay, the chair of the inquiry into child sexual abuse, was criticised by victims.
Photograph: Parliament TV

The national child abuse inquiry has been criticised by a prominent lawyer representing victims for failing to seize potentially vital caches of evidence before they are destroyed.

In a letter to the inquiry, London solicitor Imran Khan has called for records from Catholic treatment centres for problem priests, Lambeth council and even the Boston Globe newspaper – which investigated clerical abuse in the USA – to be secured.

Khan also expressed concern that some victims who are due to give evidence in criminal trials relating to abuse have been asked for fresh witness statements in a procedure that might prejudice existing prosecutions.

Khan’s letter last month , addressed to Prof Alexis Jay, chair of the independent inquiry into child sexual abuse (IICSA), warns that the inquiry should have asked relevant institutions for “all files to be retained and preserved until matters could be clarified.

“The proper procedure would have been for such a catalogue to have been produced, the inquiry to indicate which categories of documents should be retained, erring on the side of caution, and to examine documents whose relevance was not clear before confirming whether or not they should be retained.”

Khan has asked the inquiry to inform his clients who have been granted core participant status about the progress of such disclosure procedures. He wrote: “Please provide a list of the institutions that you have approached for evidence so that we may review it, take instructions on its content and make submissions if our clients are of the view that there are other bodies that should be approached.”

Both residential centres have been identified in the past as helping rehabilitate priests with a variety of problems, including alcoholism and those with engaged in paedophile activity. The Boston Globe, whose award-winning investigation of clerical abuse featured in the film Spotlight, carried out extensive enquiries into Southdown – which received priests from all around the world – and other Catholic rehabilitation centres.

Khan claimed that, following his intervention, Lambeth council halted plans to destroy documents “that were generated during periods of time that are the subject … of investigation”.

Khan has also written to the home secretary, Amber Rudd, suggesting that the burden of work being undertaken by the IICSA is so great that there should be two joint chairs of the inquiry to increase its resources.

A spokesman for the victims’ organisation White Flowers Alba, whose members have been granted core participant status, told the Guardian that the inquiry had “no idea of what they are doing legally”.

He added: “They are not telling us how they are investigating. [Jay] is not giving us updates. We have a right to a fair hearing and we are being denied that. There’s been no contact over Southdown.”

Lambeth council have promised that nothing ‘potentially relevant... has been, or will be, destroyed’ Photograph: Alamy

A Lambeth council spokesman said: “We are continuing to support the work of the independent inquiry into child sexual abuse, which as one of its 13 strands will look at the extent of any institutional failures to protect children in the care of Lambeth council from sexual abuse and exploitation.

“Lambeth council has undertaken a document review across all its stored an archived materials, under an approach that has been agreed with the inquiry’s legal team. As a result we have disclosed more than 112,000 pages from our archives.

“These documents are helping the inquiry team piece together details about how so many children were so very badly let down.

“As part of the review the council has also identified documents that are not relevant, and it has been decided in consultation with IICSA that they will be securely destroyed. The borough’s historical child abuse victim’s representation group have been kept informed throughout this process.

“No material that is potentially relevant to the inquiry has been, or will be, destroyed.”

A spokesperson for the Catholic church said that safeguarding information relating to any priests sent to Southdown is not held centrally but within individual dioceses.

A spokeswoman for IICSA said the inquiry could not comment on ongoing investigations.